xref: /openbmc/linux/tools/lib/api/fd/array.h (revision 293d5b43)
1 #ifndef __API_FD_ARRAY__
2 #define __API_FD_ARRAY__
3 
4 #include <stdio.h>
5 
6 struct pollfd;
7 
8 /**
9  * struct fdarray: Array of file descriptors
10  *
11  * @priv: Per array entry priv area, users should access just its contents,
12  *	  not set it to anything, as it is kept in synch with @entries, being
13  *	  realloc'ed, * for instance, in fdarray__{grow,filter}.
14  *
15  *	  I.e. using 'fda->priv[N].idx = * value' where N < fda->nr is ok,
16  *	  but doing 'fda->priv = malloc(M)' is not allowed.
17  */
18 struct fdarray {
19 	int	       nr;
20 	int	       nr_alloc;
21 	int	       nr_autogrow;
22 	struct pollfd *entries;
23 	union {
24 		int    idx;
25 		void   *ptr;
26 	} *priv;
27 };
28 
29 void fdarray__init(struct fdarray *fda, int nr_autogrow);
30 void fdarray__exit(struct fdarray *fda);
31 
32 struct fdarray *fdarray__new(int nr_alloc, int nr_autogrow);
33 void fdarray__delete(struct fdarray *fda);
34 
35 int fdarray__add(struct fdarray *fda, int fd, short revents);
36 int fdarray__poll(struct fdarray *fda, int timeout);
37 int fdarray__filter(struct fdarray *fda, short revents,
38 		    void (*entry_destructor)(struct fdarray *fda, int fd, void *arg),
39 		    void *arg);
40 int fdarray__grow(struct fdarray *fda, int extra);
41 int fdarray__fprintf(struct fdarray *fda, FILE *fp);
42 
43 static inline int fdarray__available_entries(struct fdarray *fda)
44 {
45 	return fda->nr_alloc - fda->nr;
46 }
47 
48 #endif /* __API_FD_ARRAY__ */
49